Big hole in the world

[OlbaiD]

Hi.

Pre-note: Dunno if this problem has been solved before because i dont know what to seach for..

I opened an old world and found this big hole in the world:

Spoiler

Show

i cannot place any blocks in hole area, also if i jump, i start falling but then i stop in mid air like stuck in something that i cant destroy and i cant move...

there was nothing built in that area

I have the last version of BTW, and this old world might have been started with +- v3.60.

what can i do to see or repair the missing area ?

thanks

[FlowerChild]

Bug reports isn't the place for this. Tech support is.